Mobile terminals comprise, for example, cellular phones and smart phones which are wide spread today and which are still developing very fast. These mobile phones allow the users to communicate via a radio network, for example cellular networks such as GSM and UMTS, the access to which is given by a network operator. While mobile phones in a first approach provide the users with audio communication, lots of mobile terminals are nowadays equipped with a more or less large screen allowing pictures and even videos to be displayed and often they are equipped with a photo camera as well. Additionally, mobile phones give access to the internet, which is a fixed communication network primarily allowing the interconnection of fixed digital communication units, e.g. personal computers. The Internet, and more precisely the World Wide Web, gives access to a multitude of websites. A website is collection of so called web pages and web applications hosted on one or more web servers. The website is connected to the internet and can be accessed by a URL (uniform resource locator), which is a digital address to the website. The user interface for accessing the website via the Internet is called web browser. A web browser is a software application that enables a user to display and interact with text, images, videos, music and other information typically located on web pages at a website on the internet or a local area network (LAN).
Mobile phones access the fixed communication network and the websites via a radio interface. A popular interface uses the wireless application protocol (WAP). WAP is an open international standard for applications that use wireless communication. It allows the internet to be accessed from a mobile terminal or device, for example a mobile phone or PDA. A so called WAP browser provides all of the basic services of a computer-based web browser but is designed to operate within the restrictions of a mobile device, such as its smaller screen size. Via the WAP browser so called WAP pages can be downloaded from a website and displayed on the mobile phone. WAP pages are typically written in, or dynamically converted to wireless markup language (WML). However, a conventional WAP browser can also display pages composed e.g. by XHTML or CHTML. As the bandwidth of the radio interface increases with new technologies more and more protocols and computer languages are also implemented in the WAP browsers which are already used in the world wide web. In the following the terms “WAP page” and “WAP pages” are synonymously used with pages statically or dynamically composed by XHTML, CHTML, etc.
Especially the young generation likes to individualize their phones with a special ring tone or original wallpaper. They interchange photos taken by themselves and download videos, full tracks (music songs) and so called video or computer games onto their mobile terminals. Multi-media content like ring tones, wallpapers, videos, video games and full tracks are provided by multi-media content providers, for example, via websites on the internet. This content is usually protected by a digital rights management system, i.e. the content is encrypted to prevent copying. While the communication via a radio network is highly standardized, the multi-media content is provided under a multitude of different digital formats and sub-formats such as MP3, WMA, WAV, OGG, VOX, MPC, AVI, JPEG, PNG, GIF, TIF, WMV, 3GP, MPEG, TIVX, ASF, HTML, XML, WML, etc which are not always compatible with each other and the constructors of phones must limit their phones to a small number of supported formats due to technical constraints. Thus, there is an incompatibility between systems providing content and mobile terminals as well as between different mobile terminals.
A user who wants to download multi-media content onto his mobile telephone must therefore make sure that the digital format, in which the multi-media content is provided, corresponds to the formats supported by his mobile. Often, the user does not know the supported formats and the technical information given in the handbook of the mobile terminal may be insufficient.
Content providers which offer multi-media content on such websites, also called portals, used to give a list of mobile phones which support the proposed content, i.e., which are compatible with the system. This does not solve the problem of incompatibility and not all users know the exact model they have, because the formats supported sometimes vary for the same model according to the version, i.e. the last software upgrade of the actual phone. Therefore, it happens quite often that multi-media content is bought by a user but cannot be displayed at the phone. It is also disappointing for the user to see an interesting content proposed and not being able to load it even after looking it up in a list. Additionally, there are still new digital formats arriving and new mobile telephone models with new features, so that these lists are not always up-to-date.
Network operators sometimes give access to multi-media content via their own website and, as they support only a limited number of phones, they try to make sure that the multi-media content proposed is compatible with these phones. Again, this does not solve the problem of incompatibility but helps only to bring together only compatible terminals with the system. This is of course not satisfactory as the user is limited in number of content and because the user is bound to his operator.
The probably most frequently used method is “trial and error”, i.e. uploading content which is afterwards not visible on the screen or which is not audible, in the case of a ring tone. This is a very frustrating and expensive solution for the user.